- Heated carbon fiber seats. Yes, on the surface, electrically heated seats may seem incongruous with a car that's about weight and driver focus not comfort and luxury, but upon closer examination they make perfect sense. They're much lighter than a heater, and although I don't expect them to fully offset the fact I've gone heaterless, given the temps I drive the car for pleasure, they should be enough to take the edge off. They'll also come in handy soothing my back in case the Tillets aren't quite as comfortable as the Westfield's MOGs for long drives.
- No Track suspension upgrade. A big concern for this car is the ability to put down power on less than ideal pavement; I don't want to get sideways on a narrow road when passing a rolling pylon. After a lot of research, I've decided to go aftermarket with shocks and springs and ordered a set of CORE dampers from Meteor Motorsport. The front are a digressive valve with linear springs while the rears are normally valved but with progressive springs. Simon believes this combination will give the best performance. For more information about why this specific combo, see the overview here.
- 3.92 rear diff rather than the longer 3.64. My dealer was unconvinced Caterham would honor the diff swap request and given I'm unsure on the shape of the torque curve on the new engine, staying stock for now seemed like the better bet. If the traction control doesn’t work well, then swapping to the 3.64 may be on the winter upgrade list next year.
- Speaking of traction control, I've decided to stick with the Emerald K6+ native TC rather than use the Race TCS system. Although I have more confidence in the latter working better, I might as well start with the cheaper option. Emerald is working on the custom ECU loom now.
- Jenvey 50mm DTHTB vs the larger 52mm. Dyno tests from Raceline and Esslinger show the smaller set flow more than enough for my power targets and should have a slight edge on idle and low-mid range given the increased air velocity. As for velocity stacks, there are only two choices in this size: 40mm and 93mm. I'd prefer to use a cold air box and not cut the bonnet, so I'm starting with the shorter set but reserve the right to make dramatic changes here based on dyno results and how I feel about the torque curve after driving the car. Longer is definitely better for all but the top of the rev range, but I'm not yet sure I'll need improvements down low.
- As for cam selection, I opted for the Esslinger Stage 4 cams. They should more than meet my power target and I do like they are an asymmetric setup vs the symmetric setup of the Raceline RDL 270 (interestingly, the more aggressive RDL 300 are asymmetric.) The downside to this choice is COVID supply chain issues. When I placed the order in mid-July I was told they were out-of-stock and would take 4-5 weeks to ship. Five months later and I still don't have an ETA on when Esslinger's cam grinder will have the blanks for my set. It's beyond frustrating.
Fortunately, the supply chain problems haven't had further impact (yet), as witnessed with the big pile of parts in my garage.